We are a dedicated group of people interested in the heritage of those family groups who historically descend from Conn Cétchathach, AKA Conn of the Hundred Battles. From the Irish annals, he was a High King of Ireland who lived ~125 AD. From him descend many of the important medieval dynasties of the northern half of Ireland, which was known as the Leath Cuinn, or the Half of Conn. We are using modern surnames and Y-DNA sequencing results to attempt to fit what the science of genetics reveals into the rich heritage of the historical Dál Cuinn genealogies. Two of the most well known Dál Cuinn dynastic groups are the Teóra Connachta and the Uí Néill. The Teóra Connachta were composed of the Uí Briúin, the Uí Fiachrach, and the Uí Ailello; this last dynasty either dying out or being exterminated in the first millennium AD. All four of these dynasties were originated by one of the sons of Eochád Muigmedón, who was descended from Conn Cétchathach and also a High King of Ireland ~350 AD. The Uí Briúin descend from Brión, the Uí Fiachrach from Fiachra, and the Uí Ailella from Ailill. These three men were full brothers from Eochád Muigmedón’s first wife Mongfind. The Uí Néill descend from Niall Noígíallach, or Niall of the Nine Hostages. He was the paternal half-brother of Brión, Fiachróe, and Ailill from Eochád Muigmedón’s second wife Cairenn Chasdub. The Y-DNA results that we have seen so far indicate that the R1b-DF104 phylogenetic node is the starting clade (Y-Haplogroup) of the Dál Cuinn. The median age estimate for R1b-DF104 places it ~36 AD. This is a little before Conn’s time frame, so there may be subclades of R1b-DF104 that are not Dál Cuinn; but R1b-DF104 is the closest major clade with an origin near to the time frame of Conn, so it was decided to be overly inclusive rather than overly exclusive. The conclusion to associate the R1b-DF104 clade with the Dál Cuinn is based on the numerous Connachta surnames in the publicly available R1b-DF104+ test results that genetically correlate very well with the historical Irish genealogies and annals for the most part. As of August 2022 AD, there are over 2050 known R1b-DF104+ men. However, some egregious discrepancies have been discovered. Some of the more crucial discrepancies are listed below: The Dál Cuinn are not descendants of Éremón; that is, our Y-DNA does not seem to match up with the other dynasties who claimed Éremón as an ancestor. The Cland Colla/Airgíalla are not Dál Cuinn. Please see the Y-Haplotree chart for the Dál Cuinn. Also please visit Peter Biggins’s excellent website for a detailed explanation of the Cland Colla Y-DNA. The Uí Maini are not a dynastic group, but appear to be a confederation of several groups. The O’Kelly chieftain line seems to be an independent branch. Please see the Y-Haplotree chart. The O’Madden seem to be most closely related to the Dál Cais ancestors, from their FTDNA project results. Many of the other "Uí Maini" families seem to be genetically Uí Briúin and Uí Fiachrach Aidne, especially the Uí Fiachrach Find among the latter. Quite unexpectedly, the Ó Maíl Álaig (Mullally) actually appear to be genetically Uí Néill, Cenél Conaill. The Uí Fiachrac Mac FirBis are not Uí Fiachrach at all, but appear to be Uí Néill, Cenél Conaill like the Ó Maíl Álaig. The Uí Briúin Aí descend from an earlier branch than the Uí Briúin Seóla and the Uí Briúin Bréifne. A member of the O’Conor Don family graciously consented to having his Y-DNA sequenced and his results fell exactly where anticipated among the Uí Briúin Aí families. But the traditional genealogy of the three brothers Dau Tengae Umae (Uí Briúin Seóla), Fergnóe (Uí Briúin Bréifne), and Eóchád Tírmchárnae (Uí Briúin Aí) is not possible genetically. While the Uí Briúin Seóla and the Uí Briúin Bréifne do descend from a common paternal ancestor, the Uí Briúin Aí had already split off before this ancestor. The best recorded explanation for this seems to be the alternative genealogy presented by Peter O’Connell and echoed by Hubert Thomas Knox in Ruaidrí Ó Flaithbertaig's A Chorographical Description Of West Or H-Iar Connaught, Hardiman, James, Editor, 1846, p. 128 and The History Of The County Of Mayo To The Close Of The Sixteenth Century, 1908, p. 382, respectively. This alternative genealogy states that Muiredach Máel had two sons: Fergus and Cathal. The Uí Briúin Seóla and Uí Briúin Bréifne descended from Fergus, as the primary genealogies have it; but then the Uí Briúin Aí must have descended from Cathal, who had one son, Fogartach. This is the only recorded explanation found for the indisputable Y-DNA split. However, there is a third major branch that shares the same paternal ancestor, likely Fergus, as the Uí Briúin Seóla and the Uí Briúin Bréifne. It is very possible this third branch is the true descendants of Eóchád Tírmchárnae, or the Maicne Eócháda Tírmchárnai. This hypothesis preserves the centuries old genealogy of the three sons of Fergus. It also explains some puzzling historical anomalies such as how Áed Flaithem was giving Annaghdown to the Church in the mid 500s AD and how the "Uí Briúin Aí" Síl Cellaig were living at Loch Cime in the mid 700s AD, as well as the Uí Briúin Bréifne. It would appear that the Uí Briúin Seóla, that is, the descendants of Fergus son of Muiredach Máel, were all living around Mag Seóla until sometime after the 700s AD when they began to split up and disperse; while the Uí Briúin Aí, that is, the descendants of Cathal son of Muiredach Máel, were all living around Mag Aí, where they remained. In summary, the current hypothesis is that there appears to have been a deliberate conflation error between Áed Flaithem son of Eóchád Tírmchárnae and likely Áed son of Fogartach, both of whom appear to have been Kings of Connacht in the same time frame. It is speculated this may have been done by the Uí Briúin Aí to strengthen their legitimacy as the dominant sept of the Uí Briúin and claim to the Kingship of Connacht in later times. The Uí Briúin Aí Síl Muiredaig and Cland Cathal split appears to have occurred soon after Fogartach rather than the almost 200 years later after Muiredach Muillethan. The Uí Briúin Aí Cland Maíl Rúanada are not Síl Muiredaig but appear to be genuinely Maicne Eócháda Tírmchárnai, not Uí Briúin Aí at all. From what we have observed, the primary problem with the traditional Irish genealogies and annals appears to be conflation and confusion errors; although there are likely deliberately introduced fictions, such as the incorrect progenitor for the Uí Briúin Aí. One classic example is in Tírechán's Collecteana where Áth Dá Loarcc is erroneously identified as being beside Kells, when in fact it was also an early name. We invite FTDNA members interested and still looking for your "place" to join. Membership is easily added and changed and one may belong to numerous FTDNA projects at the same time. In fact, it is recommended to join various FTDNA projects to assist research efforts of various areas, clans, haplogroups, SNP research projects and surname projects.